WO1988009444A1

WO1988009444A1 - A fastening device and a tool for securing the same

Info

Publication number: WO1988009444A1
Application number: PCT/NO1988/000045
Authority: WO
Inventors: Harald Kolvereid
Original assignee: Harald Kolvereid
Priority date: 1987-05-27
Filing date: 1988-05-26
Publication date: 1988-12-01
Also published as: DE3855277D1; JPH01503400A; AU1809988A; BR8807076A; EP0316417A1; CN1026516C; IN171055B; NO875052D0; NO875052L; CN1031587A; EP0316417B1; KR890701915A; SU1718732A3; ATE137844T1

Abstract

A fixing device in the shape of an outer clamping sleeve member (2, 7, 14, 18, 26, 28) with an internal thread, and an inner clamping sleeve member (3, 8, 13, 16, 24, 29) with an external thread, said clamping sleeve members being mutually rotatable. One or both clamping sleeve members may be provided with an axial through slot (19, 20, 21, 25, 30, 31) or may have mutually parallel, axially extending and partly overlapping slots (13). The threads of said clamping sleeve members may have a cylindrical or a conical shape. A central sleeve (6) may, if desired, be provided between said outer and inner clamping sleeve members for cooperation with them. If the wrench holds of said fixing device are designed as teeth and slots, a complementary securing tool (33, 34; 36, 37) may be inserted to engage said teeth and slots for mutual turning said clamping sleeve members. Utilization, e.g. to mount a shaft (5) in a wheel-hub (4), to connect pipe ends (11, 12), or as a non-threaded nut.

Description

A FASTENING DEVICE AND A TOOL FOR SECURING THE SAME

The present invention relates to a fixing device and a tool for securing the same, as stated in the preamble of the respective accompanying claims.

Dependent on its utilization, a fixing device may in one embodiment comprise a clamping sleeve for fixing cog wheels, coupling halves, inner rings of roller bearings, and the like on shafts, for joining shafts or pipes, connecting pipes in T-joints, attaching a tool to a machine, etc., and may, in a second embodiment comprise a nut for use on a non-threaded bolt.

The methods most well-known today for fixing wheels, coupling halves, and the like on shafts comprise use of keys, . adapt¬ ers, like "Taper Locks", and shrinking. The first mentioned method is labor consuming, requires_. cutting wedge-shaped grooves in the shaft as well as in the. heel, whereas the second requires much space as well as being labor consuming, although it is a simple method in case of replacement or maintenance. The third method mentioned above, i.e. shrinking is the method requiring least space. On the other hand, this method demands great accuracy in processing as well as spec- ial procedures, like heating/cooling in connection with mount ing operations which are, thus, typically carried out in a workshop.

Screw and nut are well-known fixing devices and are widely used in present technical equipment, but nut and threads also have other uses than this conventional one, e.g. a nut may be used for locking a roller bearing on a shaft.

When the mentioned fixing devices are secured it is important to ensure clamping in a controlled and reliable manner. A clamping sleeve used as a structural member represents a novelty. Practical tests, however, showed that a conventional hexagonal design of nuts provides an -unsuitable wrench hold for sleeves, and the same is the case for hook wrenches. Such wrench holds require too much axial space and/or too much thickness of sleeve material to be useful in practical cases.

It was, thus, necessary to develop new kinds of fixing devic¬ es which are especially useful for thin sleeves, like the clamping sleeve mentioned above, but also for the kind of nuts comprised by the present invention.

Figures la and lb illustrate the components of a clamping sleeve comprising an outer and an inner sleeve member. Figure 2 shows the outer sleeve and inner sleeve members according to Figure 1 in a coupled state and surrounding a shaft,

Figure 3a shows a variant of the embodiment of Figure 1 with an outer and an inner locking sleeve member, Figure 4 illustrates the clamping sleeve according to

Figures 3a and 3b in an assembled state and sur- rounding a shaft,

Figures 5a and 5b illustrate the components of a connecting coupling, and Figure 6 shows the connecting coupling in an assembled state surrounding two pipe ends, Figures 7a and 7b show a variant of the embodiments shown in Figures 5a, and 5b, respectively, Figure 8 shows the connecting coupling of Figure 7 in an assembled state surrounding two pipe ends, Figures 9a and 9b show an outer sleeve, and an inner sleeve, respectively, for a nut for use on a bolt without threads, Figures 10 and 11 show the outer portion of the nut engaged with its inner portion before, and after tighten¬ ing, respectively, Figures 12a, 12b illustrate a clamping sleeve with a wrench hold, illustrating a variant of the embodiment of Figure 1, Figure 13 illustrates the clamping s-leeve mounted on the shaft of a wheel, Figure 14 is a sectional view XIV-XIV of Figure 13,

Figures 15 and 16 show a securing tool in the shape of a lever engaged before, and after, resp. , mutually turning outer and inner sleeve 1/7 revolution, Figure 17 illustrates an alternative securing mechanism utilizing two socket spanners, Figures 18 and 19 show a front elevation, and a perspective view, respectively, of a modified securing tool for tightening the clamping sleeve as shown in Figures 12-14, Figures 20 and 21 show a partly cut away side elevation, and a plan view, respectively, of a modification of the embodiment of Figures 18 and 19. Figure 22 illustrates releasing means for heavy duty sleeves, The clamping sleeve, inter alia, shown in Figures 1-5, will simplify operations when a wheel is mounted on a shaft, since it will suffice to turn shaft and hole in the wheel hub roughly, requirements of tolerances are moderate, and rough turned surfaces provide a good hold, at the same time as mounting operations are very simple and may, thus, be carried out at the location where the equipment is, i.e. on the work¬ shop floor or on the working site.

The sleeve with cylindrical threads is advantageous in relat¬ ion to various concepts based on a cone, in that there is no relative axial movement between sleeve, shaft and wheel during tightening operations .

It should also be mentioned that the sleeve requires very little space radially as well as axially. If desired, a simple approach may be chosen with the handles of securing tools projecting only on one side of the wheel hub or bearing.

In use, a single-acting sleeve has a unique function. If it is correctly mounted it will cause the wheel, coupling, or whatever is mounted on the shaft to spin free when the shaft is subjected to a shock load in one senae of rotation. A shock load in the other direction will cause the wheel to spin more firmly onto the shaft or the shaft to break. If the wheel is mounted on two clamping sleeves having a width of half the hub, with one sleeve mounted on eacn side, shock loads will cause increased tightening of the sleeve on one or the other side, independent of the sense of rotation, alternatively to shaft fracture.

When a central clamping sleeve is used with an outer and an inner locking sleeve, it will be possible, when the design is correct, to make the wheel spin free in case of a shock load, independent of the sense of rotation.

Above examples of the performance of the coupling illustrate the special characteristics of the device. If the device is used on other rotating machine elements, e.g. couplings, outer and inner rings for roller/ball bearings, etc., unique advantages are achieved in these areas as well, as compared to conventional methods .

Connecting pipes or mounting pipes to various adapter memb¬ ers now often requires expensive and time consuming work¬ ing of the pipe ends by providing threads and/or soldering/ welding. For connecting high pressure pipes, fittings are used which are labor consuming in production due to the number of members in each joint as well as exacting demands on precision,

When the clamping sleeve principle is used on pipe fittings as indicated in Figures 5 and 6, and Figures 7 and 8, implementation involves few members, and at the same time, processing is simple in manufacture of the members because of moderate demands on tolerances . Work in connection with mount¬ ing pipes, especially hydraulic equipment, is considerably simplified by use of clamping sleeves, since use of special tools -and preparation of pipe ends is rendered unnecessary.

A clamping sleeve may be repeatedly used on used or new pipes, and with the same good result.

As shown in Figures 1 and 2, a first embodiment of the clamp¬ ing unit 1 comprises an outer sleeve 2 and an inner sleeve 3. Each sleeve has a special thread, the outer sleeve having an internal thread and the inner sleeve an external thread the shape of which ensure that when sleeves are pushed/ screwed together to stop and tightening is continued, instead of a high axial and a low radial component force, as in case of standard threads, the opposite is achieved here, i.e. a high radial and a low axial component. The thread is normally cylindrical, as shown in Figures 1-6, but it may be conical (cf. Figures 7-11), inter alia to compensate for tolerance during tightening, or to seal off the thread in an axial direction.

Figure la shows outer sleeve 2 provided in a wheel-hub 4, and Figure lb shows inner sleeve 3 provided on a shaft 5. In Figure 2 clamping sleeve 1 is illustrated with wheel-hub 4 clamped onto said axle 5. In Figure 2 the wrench holds on sleeves 2 and 3, respectively, are indicated by 2' and 3¹, respectively. The play between the thread flanks not exposed to pressure during tightening will appear from Figure 2. Also, it will appear from Figures la and lb, as well as Figure 2, that the profile of threads has a saw-tooth like shape with the pitch of tooth being less steep than its fall, e.g. as seen in Figure lb with reference to the uppermost profile .

Operations are as follows when coupling a wheel to a shaft 5 Outer or locking sleeve 2 is mounted in the wheel hub 4 and inner or locking sleeve 3 is pushed/screwed into sleeve 2 to stop. Shaft 5 is now inserted into sleeve 3 and wheel 4 is positioned as desired. Mounting operations are continued by screwing sleeve 3 into sleeve 2, outer sleeve 2 expanding until butting against hub 4, and inner sleeve 3 shrinking o hold the shaft 5. Mutual pressure will arise to lock the wheel onto the shaft. As will appear from, inter alia, Figures 3 and 4, the sleeves may be designed so as to have both wrench holds 7',8' project¬ ing on the same side of wheel-hub 4. As will appear best from Figure 4 and from Figures 3a and 3b showing the details, a central clamping sleeve 6 is used which has a wrench hold 6' . Central clamping sleeve 6 is engaged with an outer and an inner locking sleeve 7, and 8, respectively. Said cooperating sleeves will cause the wheel to spin free of the shaft dependent of the sense of rotation in case of a shock load.

In Figure 4 reference numeral 3 indicates the complete clamping device.

It will appear from Figures 3 and 4 that the thread profile is approximately corresponding to that of Figures 1 and 2. This is the case as regards the embodiment shown in Figures 5 and 6 as well. However, Figures 5 and 6 relate to a clamping sleeve 10 for connecting two pipe ends 11, 12. Pipe ends 11 and 12 are shown to be inserted in an inner sleeve 13 provided with a wrench hold 13 ' . In Figure 5a an outer or clamping sleeve 14 has a wrench hold 14' looking rather like a nut. As compared with the solid design of clamp¬ ing sleeve 14 locking sleeve 13 is thin and solid. Pipe ends 11, 12 are inserted in sleeve 13 which is provided with gasket rings or beads 15 against pipes. If sleeve 14 is pushed/ screwed onto sleeve 13 , and tightened in relation to the latter and the pipes, sleeve 13 will be firmly clamped onto pipes 11, 12 and gasket rings or beads 15 will slightly de¬ form pipes 11,12 providing further mutual attachment. This kind of coupling is, thus, also suitable for high pressure connections .

In case of clamping sleeves on pipes of a comparatively soft material, e.g. plastic or copper, clamping sleeve 13 may be thin-walled and of the same quality grade of material as the pipes, ^'whereas clamping sleeve 14 is made thick-walled or, alternatively, of a stronger material. Connections of this kind will be suitable for pipes subjected to low pressures, e.g. water pipes, and the like.

Figures 7 and 8 show a conical inner or locking sleeve 16 with a wrench hold 16', and with a plurality of rows of parallel, and overlapping slots 17, and a corresponding clamping sleeve 18 having a wrench hold 18' . It will appear that the threads are reversed as compared to the threads of sleeve 14 in Figure 5a, ^"and that the threads are conical, corresponding to locking sleeve 16 in Figure 7b. In Figure 8 the complete clamping sleeve is shown generally designated 19 and tightened O the conical thread to a stop, tightening being achieved between pipe ends 11, 12.

As mentioned, the thread, in this case, has a reversed shape as compared with the cylindircal version shown in Figure 5. The purpose of this design is to permit the nut to be pushed onto) the double cone formed by the cone and flank angle of the thread to provide for a tight fit.

If a shape like that of the cylindrical thread is selected, the cone in the thread may be used to receive tolerances, whereas the flank angle provides clamping forces.

Conical threads of fittings, for high pressure pipes, is more labor consuming than the cylindrical design mentioned above, since the manufacture of conical threads is more complicated, in addition to milling of slots. by milling.

A connection is achieved by inserting pipe ends 11 and 12 to the centre of locking sleeve 16 and in this position clamping sleeve 18 (which is already placed around pipe 11) is screwed to stop onto the conical locking sleeve. When clamping sleeve 18 is tightened further against locking sleeve 16 a connection is achieved which is tight and resists great mechanical loads in the form of vibrations and pipe knocking.

In connection with the embodiments shown in Figures 1, 2, 3b, and 7,8 it should be mentioned that outer sleeve 2 in Figure la and inner sleeve 3 of Figure lb have longitudinal slots 19, and 20, respectively, intended to render the sleeves more readily expandable in a radial direction. Consequently, the tolerances of the sleeves are not so critical as compared to requirements if there were a tight fit originally between the wheel hub 4 or shaft 5.

A corresponding concept is to be found in Figure 3b where both outer sleeve 7 and inner sleeve 8 are provided with a axial slot, generally designated 21. However, it will obviously be useless to provide intermediate sleeve 6 with such slots.

In the embodiment shown in Figure 5 there is no axial slot due to the fact that a relatively thin-walled inner sleeve is used with sealant beads or rings 15, and because a longit¬ udinal slot would, in fact, prevent a liquid sealing.

In the embodiment shown in Figure 7b liquid sealing is achieved even though axial and substantially radial slots are used, there being no open connection between various slots. This will contribute to prevent any liquid communication between the slots. At the same time, when an inner sleeve 16 of comparatively thick material is used, radial deformation will still be possible to provide a clamping effect against pipe ends 11 and 12.

Figures 9a and 9b represent a variant of the concepts illustrated in the described Figures . This embodiment is especially intended for use as a nut on a bolt without threads.

In Figure 10 the thread-less nut has reference numeral 22. Nut 22 according to the invention is pushed onto a thread-less bolt 23 against an abutment and is then tightened. By tighteni clamping force against the bolt is achieved simultaneously with thrust force on the abutment.

The nut comprises a thin-walled inner-sleeve 24, cf. Figure 9b, which may be solid or may have a longitudinal slot 25, and which has specially designed conical threads on most of its periphery as well as a wrench hold 24', and a thick-walled outer sleeve 26 having internal threads which correspond to the treads of above mentioned member 24 and having a wrench hold 26' on its periphery.

Reference numeral 27 indicates the thread showing a conicity of 2 . . In Figure 10 the outer portion 26 of nut 22 is shown in engagement with inner sleeve 24 for tightening, and in Figure 11 said members are shown after tightening, whereas ^ΔX marks outer overhang of sleeve as compared to inner sleeve.

The nut shown in Figures 9, 10, and 11 will commonly be made of steel, but may obviously be produced of other materials, e.g. brass or plastic, dependent on its utilization and the forces involved.

When outer sleeve is tightened in relation to inner sleeve the thread cone will cause a clamping force against the bolt. In Figure 10 it is shown how the outer portion 26 of the nut is set up against inner member 24, and if the outer sleeve 26 is further rotated in the same manner relative to the inner sleeve, the last mentioned will, due to the thread-cone and the slot 25 in inner sleeve 24, be firmly clamped to bolt 23. Additional tightening will, thus, cause outer member 26 to overhangΛ X outside inner member, as will appear from Figure 11. The mentioned effect may, thus, be utilized at the same time to provide a hold on the bolt and pushing force against a stop as indicated by small arrows in Figure 11.

As mentioned above, the conventional design of clamping nuts provided certain drawbacks as regards fixing. A remedy for this circumstance is indicated in Figure 12, where it is intended to be able to rotate a sleeve by the aid of a new wrench hold with the second sleeve forming a counterhold, thus, to achieve great tightening moments by simple aids. According to the invention the wrench hold is achieved by the aid of an outer sleeve 28 and an inner sleeve 29 in the shown embodiment, as shown in Figure 12a, and 12b, respectively. Each sleeve is provided wiτih a slot 30,31, respectively, and grip teeth 28' and 29', respectively. Outer sleeve 28 and inner sleeve 29 may have an equal or different number of teeth 28', 29', the number of teeth, inter alia, depending on the difference of sleeve diameter. If outer sleeve 28 and inner sleeve 29 have a different number of teeth/slots, one sleeve 0 may be rotated relative to the other by the aid of a securing tool, e.g. a lever 32, as clearly seen in Figures 15 and_16. Alternatively, if tightening moments become large, it is possibl to use spanners 33 and 34 for the outer, and inner sleeve, respectively (to avoid fracturing of the teeth) . Such spanners 5 will be adapted to the slots and teeth of the respective sleeves and may, e.g. extend over approximately half of the circumference of the sleeves, as indicated in Figure 17.

Figures 12a and 12b, as mentioned, show the outer sleeve 28

20 and inner sleeve 29, whereas Figure 13 shows an axle mounted in a wheel-hub 4, and Figure 14 shows a cross section of the wrench hold portion with said axle 5 being surrounded.

Figures 15 and 16 show how the bar is engaged with sleeves 25.- 28,29, before, and after one of the sleeves (29) is turned r/7 of a revolution as compared to the other.

In order to mount wheels on shafts sleeve 28 is at first pushed/screwed to stop on sleeve 29. Then the combined sleeve 3_Q 28,29 is pushed into the hub 4 and shaft 5 is inserted into sleeve/hub. After adjusting the wheel on its shaftthe sleeve is tightened by the aid of bar 32.

Operations for tightening sleeves by the aid of a bar 32 are 35 as follows. In Figures 15 and 16 capital letters indicate the openings in outer sleeve 28, and small letters indicate the openings in inner sleeve 29. It will appear from Figure 15 that openings A,a are aligned, whereas openings B,b are slightly displaced relative to each other. Position B/b will, thus, form a starting point for placing a bar 32. When bar 32 is manipulated a position as shown in Figure 16 will occur, with openings B, b aligned, whereas openings C,c form a new starting point for placing the bar. By carrying on in this manner until totally 7 bar operations are carried out, opening b will be aligned with opening A, and outer sleeve 28 is now rotated in relation to inner sleeve 29 correspond¬ ing to a sector a b. These operations may continue until the desired torque is achieved by the aid of said tool. By providing bar 32 with a torque indicator it is possible to carry out a completely controlled tightening operation. In stead of utilizing a bar for tightening, socket spanners 33,34 may, alternatively, be used, as indicated in Figure 17. If it is desired to lock the sleeves mutually in addition to the locking effect provided by friction, a locking pin 35, as shown in Figure 14 may be mounted.

It might, however, be advantageous to use other kinds of securing tools, as illustrated in Figure 18. In this case, two substantially coaxial and mutually rotatable spanner means are used which comprise an outer socket spanner 36, having a wrench hold 36', and an inner socket spanner 37 having a wrench hold 37' . Outer wrench hold is provided with a row of teeth 38 intended for engagement with slots 39 between teeth 28, as shown in Figures 12a and 14. In the same manner inner socket spanner 37 is provided with a row or a ring of teeth 40 intended to engage in slots 41 between teeth 29', cf. Figures 12b and 14.

By using common socket spanners or mechanized, hydraulic, electric, or pneumatic wrenches which can engage wrench holds 36' and 37', powerful tightening of the clamping nut shown in Figures 12-14, may be achieved in a simple manner. It will be obvious in this connection that by substituting conventional wrench holds, as shown in some of the above described Figures,the securing tool shown in Figures 18 and 19 may readily be used for such devices .-.This fact is especially relevant in case it is. suitable to operate^" a securing tool only from one side, as indicated in Figures 4 and 10, as well as in Figures 12-14.

It will be understood from the above that the fixing device according to the present invention may be used for a number of tasks, e.g. locking wheel-hubs and coupling halves onto shafts, connecting shafts, connecting pipes made of steel, other metals, plastic, etc. The sleeves according to the invention may be massive, but showing different strength as an alternative to being provided with the mentioned slots. By the aid of- the non-threaded nut attachment fixing is achieved,in a most simple manner, due to the fact that both high axial and high radial force components are achieved. By using wrench holds,as indicated in Figures 12-14, and in connection with fixing tools, as indicated in Figures 15-19, the torque exerted by the used tool will be evenly distributed at the same time as the teeth on inner and outer sleeve permit locking against unintentional rotation of one sleeve in relation to the other. If the number of teeth on inner and outer sleeve differ locking may be achieved with very slight adjustments of the tightening moment.

In Figures 20 and 21 a modification of the embodiment of ' Figures 18 and 19 is shown. Outer socket spanner 36" has a wrench hold 42 and inner socket spanner 37" has a wrench hold 43. Even though this is not to be considered as limiting the scope of the invention, wrench holds 42 and 43 may have the same dimension. The performance is as disclosed in connection with Figures 18 and 19. Reference numeral 5 indicates a shaft, e.g. as shown in Figure 14.

In Figure 22 it is illustrated how heavy duty clamping sleeves can be released by introducing pressurized oil into grooves 42 on the threads of one or both of said sleeves, said grooves communicating with axially extending presurized oil inlets in said at least one sleeve.

Claims

CLAIMS :

1. A fixing device to be located between machine elements such as a wheel hub and a shaft, comprising an outer clamping sleeve member and an inner clamping sleeve member, one coaxially encompassing the other, said sleeves upon mutual rotation interlocking said machine elements by

• frictional forces.

2. A fixing device according to claim 1, wherein the outer sleeve member has an internal cylindrical thread and the inner sleeve member has an external cylindrical thread to develop upon mutual tightening against a stop of said sleeve members, high radial, but low axial force components.

3. A fixing device according to claim 1 or 2, wherein each sleeve member has at least one axially extending through slot.

4. A fixing device in the shape of an outer clamping sleeve member with an internal thread, and an inner clamping sleeve member with an external thread, said clamping sleeve members being mutually rotatable, wherein each clamping sleeve member has at least one axially extending through slot in order to develop high radial, but low axial force components when the clamping sleeve members are mutually tightened against a stop.

5. A fixing device according to claim 4, wherein said clamping sleeve members are designed to have their wrench holds at a mutual distance substantially corresponding to the axial extent of said threads.

6. A fixing device according to claim 1 or 4 , wherein a central clamping sleeve with internal and external threads being designed for cooperation with the threads of the inner clamping sleeve member and the outer clamping sleeve member, respectively, is provided between the external thread of inner clamping sleeve member and the internal thread of outer clamping sleeve member.

7. A fixing device according to claims 1 and 3 , wherein the wrench holds of inner clamping sleeve member and outer clamping sleeve member are adjacent when said sleeve members are cooperating with central clamping sleeve, the wrench hold of central clamping sleeve extending at a distance from said

^"10 clamping sleeve wrench holds approximately corresponding to the axial extent of threads of the respective clamping sleeve members.

8. A fixing device according to claim 1 or 4, wherein

15 said clamping sleeve members are designed in such a manner that the wrench hold on the clamping sleeve members consists of teeth with slots extending between said teeth.

9. A fixing device according- o claim 8, wherein said

20 wrench holds of said clamping sleeve members are provided on the same side of the fixing device._.

10. A fixing device for joining elements, of circular - cross section, e.g. two pipe ends, comprising an outer .₂₅ clamping sleeve member and an inner clamping sleeve member, one coaxially encompassing the other, said inner sleeve member encompassing and contacting said pipe ends and said members upon mutual rotation interlocking said elements.

₃0 11- fixing device according to claim 10, wherein the outer clamping sleeve member has an internal thread and the inner clamping sleeve member has an external thread, said members upon mutual rotation developing high radial and low axial force components when said members are tightenened

₃₅ against a stop. 12. A fixing device according to claim 10, wherein the outer clamping sleeve member has a conical internal thread and the inner clamping sleeve member has a conical external thread.

I

13. A fixing device according to claim 11 or 12 , wherein said outer sleeve member consists of a strong sleeve and said inner sleeve member consists of a substantially, weaker sleeve, said inner sleeve on its inner surface having at least two gasket rings or beads which engage and possibly deform the circumference of the respective elements when said clamping sleeve members are mutually tightened.

14. A fixing device having an outer claming sleeve member with an internal thread, and an inner clamping sleeve member with an external thread, said clamping sleeve members being mutually rotatable, suitably for connecting elements which have a circular cross section, e.g.,two pipe ends, wherein said outer clamping sleeve member consists of a strong clamping sleeve (14) , and that the inner clamping sleeve member consists of a substantially weaker locking sleeve (13) which on its inside is provided with at least two gasket rings or beads (15) which engage and possibly . deform the circumference of the respective elements when said clamping sleeve members (14, 13) are mutually tightened.

15. A fixing device having an outer clamping sleeve member with an internal thread, and an inner clamping sleeve member with an external thread, said clamping sleeve members being mutually rotatable, wherein said inner clamping sleeve member has an external conical structure and that said outer clamping sleeve member exhibits the same internal conical shape.

16. A fixing device according to claim 12, 13 or 15, preferably for connecting members with a cylindrical cross section, e.g. two pipe ends, wherein the inner clamping sleeve is provided with several rows of parallel axially extending slots which overlap.

17. A fixing device according to claim 12, 13 or 15, especially for use as a non-threaded nut, wherein said inner clamping sleeve member is provided with an axially extending through slot in order to develop a high axial and a high radial force component against a stop, and a internal structural member, respectively, when said clamping sleeve members are mutually tightened.

18. A fixing device according to claims 12, 13 , 15 or 17 , wherein said inner sleeve is designed with corru¬ gations on its inner face.

19. A fixing device according to anyone of the preceeding claims, wherein the thread surface of at least one of said sleeve members is provided with a narrow groove communicating with axially extending pressurized oil inlets 0 located in said at least one sleeve member.

20. A securing tool for tightening a fixing device, said device comprising an outer clamping sleeve member with an internal thread and an inner clamping sleeve member with ₅ an external thread, and with each clamping sleeve member being provided with a wrench hold located at the same side of said fixing device, and with each wrench hold consisting of a number of teeth with intermediate slots, wherein two mutually movable tool members having a number of teeth are mutually o spaced to be insertable into said wrench hold slots, mutual rotation of said two tool members causing the members of the fixing device to be mutually tightened.

21. A securing tool according to claim 20, wherein ₅ said tool members comprise an inner socket spanner, and an outer socket spanner which are coaxially arranged and are mutually rotatable, and each being provided with a wrench hold for cooperation with means for mutually moving said socket spanners.

22. A securing tool for tightening a fixing device which comprises an outer clamping sleeve member with an internal thread, and an inner clamping sleeve member with an external thread, which clamping sleeve members are mutually rotatable and each have a wrench hold on the same side of the fixing device in the shape of a number of teeth and slots, wherein a bar is insertable into two adjacent slots in said outer clamping sleeve member, and inner clamping sleeve member, respectively, said bar with one face thereof contacting a tooth on said outer clamping sleeve member and with its other face contacting a tooth on said inner clamping sleeve, and when moved across the longitudinal axis of said bar causing said two clamping sleeve members to turn.